This application claims priority under 35 U.S.C. xc2xa7xc2xa7119 and/or 365 to 9802143-9 filed in Sweden on Jun. 16, 1998; the entire content of which is hereby incorporated by reference.
The present invention relates to a device and to a method for protecting an object, and more specifically for protecting, for instance, an antenna or a microbase station from mechanical damage as the antenna or station is hoisted up or lowered down along a vertical structure, for instance a mast or the wall of a building.
Various types of objects are lifted up or lowered down along vertical structures, such as along masts or the walls of buildings for instance, in many different connections. One example in this respect is found in the installation and maintenance of base stations and antennas in mobile telephone networks. When hoisting and lowering equipment up and down masts, walls and other vertically extending structures in conjunction with either mounting or dismantling said equipment, there is a risk of mechanical damage being caused to the equipment itself, and also to objects such as windows, walls, etc., that are struck or scraped by the equipment as it is raised or lowered.
British Patent Application GB 2 174 059 describes a beer barrel provided with an inflatable barrel rolling ring for use in rolling the barrel, for instance when loading/unloading a brewery truck. The ring is fitted over the barrel with the ring deflated and is then inflated. The outer wall of the ring is comprised of a material that has a high coefficient of friction and, when inflated, the ring is held firmly to the barrel by the frictional forces acting between the barrel and the ring. The invention described in GB 2 174 059 is highly advantageous with respect to traditional beer barrels, since it enables the barrel to be given a simpler design and to be produced more cheaply, since it is unnecessary to pay the cost of repairing rolling rings that become damaged when handling the barrel, while the fact that the rolling ring can be removed when not needing to roll the barrel means that the barrel will take-up less space in a storeroom and on brewery trucks.
The present invention addresses the problem of protecting an object from mechanical damage, for instance radio equipment, as it is lifted up or lowered down a vertically extending structure, such as a mast or a wall for instance.
Another problem addressed by the invention is that of protecting the structure along which the object is moved from mechanical damage during the actual process of lifting or lowering the object.
These problems are solved generally in accordance with the invention with the aid of a method wherein the object is fitted with a protective device in the form of two inflatable tubes prior to moving object up or down the wall of a building. The protective device functions as a bumper or fender between object and wall as the object is raised or lowered. The invention relates both to a method for protecting the object and to the protective device. More specifically, the problems are solved by placing around the object at least one protective device which includes a first inflatable tube which is fastened to a second inflatable tube. The tubes are positioned so as to form two concentrical rings or spirals around the object, with the first tube located inwardly of the second tube. The first tube is filled with an appropriate amount of gas, preferably air, so as to be brought into contact with the object and to hold the protective device firmly to said object through the medium of frictional forces. The second tube is filled with an appropriate amount of gas, preferably air, such that the second tube will function as a fender or bumper between object and wall.
An object of the present invention is to provide a method and a device for protecting an object as it is lifted up or lowered down a vertically extending structure, such as the wall of a building or a mast, and also for protecting the structure along which the object is lifted or lowered from mechanical damage.
A further object of the invention is to provide a method of protecting the object and the structure along which the object is lifted or lowered that is flexible and can be readily put into effect.
One advantage afforded by the invention is that it affords a simple and flexible method of protecting an object as it is lifted up or lowered down a vertical structure, such as the wall of a building or a mast, and also of protecting the structure along which the object is raised or lowered from mechanical damage.
Another advantage afforded by the invention is that the use of an inner and an outer tube around the object enables the respective tubes to be optimised for the purpose of holding the device firmly to the object by friction and of acting as a bumper between said object and said structure.
A further advantage afforded by the invention is that the protective device will only take up a small amount of space when deflated, therewith enabling the device to be transported and stored easily and conveniently.
The invention will now be described in more detail with reference to preferred embodiments thereof and also with reference to the accompanying drawings.